The North Brazil Continental Shelf (NBCS) is characterized by high biological production associated with biogeochemical processes controlled by the interaction between river discharge and oceanic circulation. This interaction can be reflected in the variability of salinity in the continental shelf. The present study aims to create an empirical model of salinity and investigate the connections between salinity and primary productivity along the coastal and adjacent oceanic regions of NBCS. The salinity model was created with in situ data and satellite images. The resulting in situ-based salinity surfaces were compared with salinity images acquired by CONAE’s SAC-D/Aquarius and ESA’s SMOS/MIRAS satellites. The relative influence of salinity on primary productivity was investigated through an adjustment of a function that best represent the behavior of the variables. The salinity model showed results consistent with the Aquarius and SMOS satellite. The relationship between marine oceanic primary Productivity and salinity in coastal region presents a complex behavior which suffers continent and ocean influence differently in space.